tyre

The Oxford English Dictionary suggests that the word derives from attire, while other sources suggest a connection with the verb totie. The spelling tyre is used in the United Kingdom, Ireland, Australia, and New Zealand after being revived in the 19th century. Both tyre and tire were used in the 15th and 16th centuries. The United States did not adopt the revival of tyre, and tire is the only spelling currently used there and in Canada.